Inflatable ball

ABSTRACT

An inflatable ball includes an outer cover defining a confining chamber therein, a bladder unit disposed in the confining chamber, and a valve unit connected to the bladder unit. The bladder unit includes an outer bladder defining an accommodation chamber, an inner bladder disposed in the accommodation chamber and defining an inflating space, and a winding thread layer disposed in the accommodation chamber and covering an outer surrounding surface of the inner bladder. The outer bladder has a first elongation percentage. The inner bladder has a second elongation percentage greater than the first elongation percentage of the outer bladder. The winding thread layer has a third elongation percentage less than the first elongation percentage of the outer bladder. The bladder unit can be deflated and inflated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a ball, more particularly to an inflatable ball.

2. Description of the Related Art

Referring to FIG. 1, a conventional inflatable ball includes an outer cover 1, a rubber bladder layer 2 that is disposed in the outer cover 1, and a valve unit 3 that is provided on the rubber bladder layer 2, and that extends through the rubber bladder layer 2 and the outer cover 1. The valve unit 3 includes a base portion 301 that is connected fixedly to an inner surface of the rubber bladder layer 2, and a valve portion 302 that is inserted in the base portion 301. Consequently, when the rubber bladder layer 2 is inflated by pumping air into an internal space defined by the rubber bladder layer 2 through the valve unit 3, the inflatable ball can be used.

However, the conventional inflatable ball has the following disadvantages. Since the rubber bladder layer 2 is made by vulcanizing a rubber material, the rubber bladder layer 2 may be over-inflated. Therefore, the inflatable ball may tend to lose a desired shape thereof. Furthermore, the rubber bladder layer 2 is made from a single layer of rubber such that a leakage problem is likely to occur. In addition, since the base portion 301 of the valve unit 3 is made from an elastic rubber material, the valve portion 302 may be moved through the base portion 301 and thus falls into the internal space defined by the rubber bladder layer 2 when being inserted into the base portion 301.

Referring to FIG. 2, another conventional inflatable ball includes an outer cover 1 that is made by sewing a plurality of leather materials, a bladder unit 4 that is disposed in the outer cover 1, and a valve unit 3 that is provided on the bladder unit 4, and that extends through the bladder unit 4 and the outer cover 1. The bladder unit 4 includes a rubber layer 401 and a winding thread layer 402 that surrounds the rubber layer 401. The winding thread layer 402 is made from a plurality of threads and is able to prevent the rubber layer 401 from being over-inflated.

Nevertheless, the conventional inflatable ball shown in FIG. 2 has the following drawbacks. Sine the winding thread layer 402 is bonded to the rubber layer 401 via an adhesive, the outer cover 1 may contact the adhesive on the winding thread layer 402 such that the outer cover 1 may become yellowish. Accordingly, the physical appearance of the inflatable ball may be negatively influenced. Moreover, when the bladder unit 4 is inflated, the threads of the winding thread layer 402 may be embedded into seams of the leather materials of the outer cover 1, thereby adversely affecting ease of inflation of the rubber layer 401. As a result, a force is required to be exerted on the outer cover 1 for adjusting the same during inflation so as to prevent the threads from being embedded in the seams of the leather materials of the outer cover 1. Besides, the winding thread layer 402 may absorb liquid (e.g., water and sweat) penetrating the outer cover 1 such that a weight of the inflatable ball is likely to vary.

Referring to FIG. 3, yet another conventional inflatable ball (disclosed in U.S. Pat. No. 7,517,294 B2) includes an outer cover 1, a bladder unit 5 that is disposed in the outer cover 1, and a valve unit 3 that is provided on the bladder unit 5, and that extends through the bladder unit 5 and the outer cover 1. The bladder unit 5 includes an inner bladder 501 that is made from a rubber material, and an outer bladder 502 that is made from thermoplastic polyurethane (TPU) and that has an elongation percentage smaller than that of the inner bladder 501. When the bladder unit 5 is inflated, the outer bladder 502 is able to limit inflation of the inner bladder 501 and hence prevents the same from being over-inflated.

The outer bladder 502 of this conventional inflatable ball illustrated in FIG. 3 is able to replace the winding thread layer 402 of the conventional inflatable ball illustrated in FIG. 2 in terms of the aforementioned drawbacks of the winding thread layer 402. Nonetheless, strength of the outer bladder 502 is generally weaker than that of the winding thread layer 402. Thus, impact strength of the inflatable ball illustrated in FIG. 3 is required to be enhanced for meeting a requirement of an official organization (e.g., FIFA) for official match balls. A plurality of reinforcing fabric layers (not shown) that have high tensile strength can be attached to an inner surface of the outer cover 1, but may increase cost of production.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an inflatable ball that can overcome the aforesaid drawbacks of the prior arts.

According to this invention, an inflatable ball includes an outer cover, a bladder unit, and a valve unit. The outer cover defines a confining chamber therein and is formed with a through-hole. The bladder unit is disposed in the confining chamber, and includes an outer bladder, an inner bladder, and a winding thread layer. The outer bladder defines an accommodation chamber and is formed with a through-hole registered with the through-hole of the outer cover. The inner bladder is disposed in the accommodation chamber, defines an inflating space, and is formed with a through-hole registered with the through-hole of the outer bladder. The inner bladder has an inner surrounding surface that confronts the inflating space, and an outer surrounding surface that is opposite to the inner surrounding surface. The winding thread layer is disposed in the accommodation chamber and covers the outer surrounding surface of the inner bladder. The outer bladder has a first elongation percentage. The inner bladder has a second elongation percentage greater than the first elongation percentage of the outer bladder. The winding thread layer has a third elongation percentage less than the first elongation percentage of the outer bladder. The bladder unit is operable between a deflated state, where the outer bladder and the winding thread layer cooperatively define a gap therebetween, and an inflated state, where the winding thread layer abuts against the outer bladder. The valve unit is connected to the bladder unit at a position corresponding to the through-hole of the outer bladder and the through-hole of the outer cover.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment of this invention, with reference to the accompanying drawings, in which:

FIG. 1 is a fragmentary partly sectional view of a conventional inflatable ball;

FIG. 2 is a fragmentary partly sectional view of another conventional inflatable ball;

FIG. 3 is a sectional view of yet another conventional inflatable ball;

FIG. 4 is a sectional view to illustrate the preferred embodiment of an inflatable ball at a deflated state according to this invention;

FIG. 5 is an enlarged fragmentary sectional view of the preferred embodiment; and

FIG. 6 is a view similar to FIG. 4, but illustrating the preferred embodiment at an inflated state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 4, 5, and 6, the preferred embodiment of an inflatable ball according to the present invention includes an outer cover 10, a bladder unit 20, and a valve unit 30.

The outer cover 10 defines a confining chamber 13 therein and is formed with a through-hole 12. In this embodiment, the outer cover 10 is made by sewing pieces of leather materials.

The bladder unit 20 is disposed in the confining chamber 13 and includes an outer bladder 21, an inner bladder 22, and a winding thread layer 23.

The outer bladder 21 defines an accommodation chamber 24, and has an internal surrounding surface 213 that faces the accommodation chamber 24, an external surrounding surface 214 that is disposed radially opposite to the internal surrounding surface 213, and a hole-defining portion 211 that is formed with a through-hole 212 registered with the through-hole 12 of the outer cover 10. The inner bladder 22 is disposed in the accommodation chamber 24, defines an inflating space 25, and has an inner surrounding surface 223 that confronts the inflating space 25, an outer surrounding surface 224 that is opposite to the inner surrounding surface 223, and a hole-defining portion 221 that is formed with a through-hole 222 registered with the through-hole 212 of the outer bladder 21. The hole-defining portion 221 of the inner bladder 22 is connected to the hole-defining portion 211 of the outer bladder 21. The outer bladder 21 has a first elongation percentage, and the inner bladder 22 has a second elongation percentage that is greater than the first elongation percentage of the outer bladder 21.

The outer bladder 21 is made from a material selected from the group consisting of thermoplastic polyurethane (TPU), polyvinyl chloride (PVC), ethylene-vinyl acetate (EVA), natural rubber, artificial rubber, and latex. The inner bladder 22 is made from a material selected from the group consisting of TPU, PVC, EVA, natural rubber, artificial rubber, and latex. The materials for the outer and inner bladders 21,22 can be chosen based on actual requirements as long as the second elongation percentage of the inner bladder 22 is greater than the first elongation percentage of the outer bladder 21. In this embodiment, the outer bladder 21 is made from a plurality of TPU pieces joined together using high frequency or ultrasonic welding techniques. The inner bladder 22 in this embodiment is made from vulcanized rubber. It should be noted that the inner bladder 22 could be made from a plurality of pieces (e.g., TPU pieces, PVC pieces, or EVA pieces) joined together using high frequency or ultrasonic welding techniques in other embodiments.

The winding thread layer 23 is disposed in the accommodation chamber 24 and covers the outer surrounding surface 224 of the inner bladder 22. In this embodiment, the winding thread layer 23 is made from a plurality of threads and has a third elongation percentage that is less than the first elongation percentage of the outer bladder 21. The winding thread layer 23 is bonded to the outer surrounding surface 224 of the inner bladder 22 via an adhesive.

The bladder unit 20 is operable between a deflated state (see FIG. 4), where the winding thread layer 23 and the internal surrounding surface 213 of the outer bladder 21 cooperatively define a gap 26 therebetween, and an inflated state (see FIG. 6), where the winding thread layer 23 abuts against the internal surrounding surface 213 of the outer bladder 21.

The valve unit 30 is connected to the bladder unit 20 and has a portion that extends outwardly through the through-hole 12 of the outer cover 10, and an opposite portion that extends inwardly into the inflating space 25 through the through-hole 212 of the outer bladder 21, the winding thread layer 23, and the through-hole 222 of the inner bladder 22. The valve unit 30 includes a hollow valve-supporting seat 31 that is connected to the hole-defining portion 221 of the inner bladder 22, a hollow valve-retaining member 32 that is connected to the hole-defining portion 211 of the outer bladder 21, and a slit-type valve 33 that is disposed in the valve-retaining member 32.

The valve-supporting seat 31 has a rim portion 311 that is mounted to the inner surrounding surface 223 of the inner bladder 22, and a base portion 312 that extends radially and inwardly from the rim portion 311 of the valve-supporting seat 31, and that defines a retaining space 313 in spatial communication with the inflating space 25. The retaining space 313 has an annular section 314 that has a radius larger than that of the other portion of the retaining space 313. It should be noted that the rim portion 311 of the valve-supporting seat 31 could be mounted to the winding thread layer 23 in other embodiments.

The valve-retaining member 32 has a rim portion 321 that is mounted to the external surrounding surface 214 of the outer bladder 21, and a base portion 322 that extends radially and inwardly from the rim portion 321 of the valve-retaining member 32, that extends fittingly into the retaining space 313 in the base portion 312 of the valve-supporting seat 31 through the through-hole 212 of the outer bladder 21, the winding thread layer 23, and the through-hole 222 of the inner bladder 22, and that defines a retaining groove 323 in spatial communication with the retaining space 313. The base portion 322 of the valve-retaining member 32 has a shoulder 324 that is fitted into the annular section 314 of the retaining space 313 of the valve-supporting seat 31 and that defines an annular part 325 of the retaining groove 323 thereof. It should be noted that the rim portion 321 of the valve-retaining member 32 could be mounted to the internal surrounding surface 213 of the outer bladder 21 in other embodiments.

The slit-type valve 33 has an outer valve portion 331 that extends radially and outwardly through the through-hole 12 of the outer cover 10, and an inner valve portion 332 that extends radially, inwardly, and fittingly into the retaining groove 323 in the valve-retaining member 32 through the through-hole 212 of the outer bladder 21, the winding thread layer 23, and the through-hole 222 of the inner bladder 22. The inner valve portion 332 has an annular protrusion 334 that is received fittingly in the annular part 325 of the retaining groove 323 of the valve-retaining member 32. The slit-type valve 33 is formed with a vent hole 333 that extends radially through the outer and inner valve portions 331,332 thereof, and that is in spatial communication with the retaining groove 323. Therefore, air can be pumped into the inflating space 25 through the valve unit 3 so as to move the bladder unit 20 to the inflated state.

In this embodiment, the valve-supporting seat 31 is made from a material the same as the material of the inner bladder 22. The valve-retaining member 32 is made from a material the same as the material of the outer bladder 21, and is secured to the outer bladder 21 by virtue of high frequency or ultrasonic welding techniques. The slit-type valve 33 is made from rubber. It should be noted that the valve-supporting seat 31 could be made from a material different from the material of the inner bladder 22 in other embodiments as long as the valve-supporting seat 31 could be connected to the inner bladder 22, and that the valve-retaining member 32 could be made from a material different from the material of the outer bladder 21 in other embodiments as long as the valve-retaining member 32 could be connected to the outer bladder 21.

Some of the advantages of the inflatable ball of this invention are as follows:

1. Since the first elongation percentage of the outer bladder 21 is smaller than the second elongation percentage of the inner bladder 22, and the third elongation percentage of the winding thread layer 23 is smaller than the first elongation percentage of the outer bladder 21, both of the outer bladder 21 and the winding thread layer 23 are able to limit the inner bladder 22 and prevent the same from over-inflation. Therefore, the outer bladder 21 and the winding thread layer 23 are capable of maintaining the inner bladder 22 at a desired size and a desired shape. The outer cover 10 can be further prevented from being improperly deformed. Besides, when the bladder unit 20 is at the inflated state, pressure exerted on the outer cover 10 by the bladder unit 20 can be controlled such that sewing threads of the outer cover 10 are not damaged by the pressure exerted by the bladder unit 20. The inflatable ball can be hence made by means of machine sewing threads or hand sewing threads.

2. Compared to the conventional inflatable ball of U.S. Pat. No. 7,517,294 B2, the disposition of the winding thread layer 23 effectively enhances the strength of the bladder unit 20, thereby meeting an impact strength requirement of an official organization such as FIFA. Therefore, reinforcing fabric layers that have high tensile strength are not necessary to be attached to an inner surface of the outer cover 10.

3. The outer bladder 21 is disposed between the winding thread layer 23 and the outer cover 10, and is hence able to prevent the outer cover 10 from contacting the adhesive on the winding thread layer 23. Accordingly, the outer cover 10 is prevented from becoming yellowish, and a good physical appearance of the inflatable ball is sustained. Moreover, the outer bladder 21 is capable of preventing the threads of the winding thread layer 23 from being embedded in seams of the leather materials of the outer cover 10 such that the bladder unit 20 can be smoothly inflated. The outer bladder 21 can also prevent the winding thread layer 23 from absorbing liquid penetrating the outer cover 10, thereby maintaining a weight of the inflatable ball.

4. The outer bladder 21 and the valve unit 30 cooperate to seal the inner bladder 22 so that the inner bladder 22 has better gas-tightness compared to the conventional rubber bladder layer 2 (see FIG. 1) and the conventional bladder unit 4 (see FIG. 2). Leakage is unlikely to happen.

5. Since the valve-retaining member 32 in this embodiment is made from a TPU material that is not easily elastically deformable compared to a rubber material, and the annular protrusion 334 of the slit-type valve 33 is received fittingly in the annular part 325 of the retaining groove 323 of the valve-retaining member 32, falling of the slit-type valve 33 into the inflating space 25 of the inner bladder 22 can be avoided.

6. The outer bladder 21 and the winding thread layer 23 are able to protect the inner bladder 22, thereby enhancing the durability of the bladder unit 20.

7. By choosing different materials for the outer bladder 21, the inflatable ball can be formed to have a desired thickness and a desired hardness. Consequently, the inflatable ball of this invention can be embodied as an inflatable sports ball such as a soccer ball, a volleyball, a basketball, a rugby ball, etc.

While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation and equivalent arrangements. 

1. An inflatable ball comprising: an outer cover defining a confining chamber therein and formed with a through-hole; a bladder unit disposed in said confining chamber and including an outer bladder that defines an accommodation chamber and that is formed with a through-hole registered with said through-hole of said outer cover, an inner bladder that is disposed in said accommodation chamber, that defines an inflating space, and that is formed with a through-hole registered with said through-hole of said outer bladder, said inner bladder having an inner surrounding surface that confronts said inflating space, and an outer surrounding surface that is opposite to said inner surrounding surface, and a winding thread layer that is disposed in said accommodation chamber and that covers said outer surrounding surface of said inner bladder; wherein said outer bladder has a first elongation percentage, said inner bladder has a second elongation percentage greater than the first elongation percentage of said outer bladder, and said winding thread layer has a third elongation percentage less than the first elongation percentage of said outer bladder; wherein said bladder unit is operable between a deflated state, where said outer bladder and said winding thread layer cooperatively define a gap therebetween, and an inflated state, where said winding thread layer abuts against said outer bladder; and a valve unit connected to said bladder unit at a position corresponding to said through-hole of said outer bladder and said through-hole of said outer cover.
 2. The inflatable ball as claimed in claim 1, wherein said valve unit has a portion extending outwardly through said through-hole of said outer cover, and an opposite portion extending inwardly into said inflating space through said through-hole of said outer bladder, said winding thread layer, and said through-hole of said inner bladder.
 3. The inflatable ball as claimed in claim 1, wherein said outer bladder is made from a material selected from the group consisting of thermoplastic polyurethane, polyvinyl chloride, and ethylene-vinyl acetate.
 4. The inflatable ball as claimed in claim 1, wherein said outer bladder is made from a material selected from the group consisting of natural rubber, artificial rubber, and latex.
 5. The inflatable ball as claimed in claim 1, wherein said inner bladder is made from a material selected from the group consisting of thermoplastic polyurethane, polyvinyl chloride, and ethylene-vinyl acetate.
 6. The inflatable ball as claimed in claim 1, wherein said inner bladder is made from a material selected from the group consisting of natural rubber, artificial rubber, and latex.
 7. The inflatable ball as claimed in claim 1, wherein: said outer bladder has an internal surrounding surface facing said winding thread layer, and an external surrounding surface disposed radially opposite to said internal surrounding surface; and said valve unit includes a hollow valve-supporting seat having a rim portion that is mounted to one of said inner surrounding surface of said inner bladder and said winding thread layer, and a base portion that extends radially and inwardly from said rim portion of said valve-supporting seat, and that defines a retaining space in spatial communication with said inflating space, a hollow valve-retaining member having a rim portion that is mounted to one of said internal and external surrounding surfaces of said outer bladder, and a base portion that extends radially and inwardly from said rim portion of said valve-retaining member, that extends fittingly into said retaining space in said base portion of said valve-supporting seat, and that defines a retaining groove in spatial communication with said retaining space, and a slit-type valve having an outer valve portion that extends radially and outwardly through said through-hole of said outer cover, and an inner valve portion that extends radially, inwardly, and fittingly into said retaining groove in said valve-retaining member through said through-hole of said outer bladder, said winding thread layer, and said through-hole of said inner bladder, said slit-type valve being formed with a vent hole that extends radially through said outer and inner valve portions thereof, and that is in spatial communication with said retaining groove.
 8. The inflatable ball as claimed in claim 7, wherein said retaining space of said valve-supporting seat has an annular section, said base portion of said valve-retaining member having a shoulder that is fitted into said annular section of said retaining space of said valve-supporting seat and that defines an annular part of said retaining groove thereof, said slit-type valve having an annular protrusion that is received fittingly in said annular part of said retaining groove of said valve-retaining member.
 9. The inflatable ball as claimed in claim 7, wherein said valve-supporting seat is made from a material the same as the material of said inner bladder.
 10. The inflatable ball as claimed in claim 7, wherein said valve-supporting seat is made from a material different from the material of said inner bladder.
 11. The inflatable ball as claimed in claim 7, wherein said valve-retaining member is made from a material the same as the material of said outer bladder.
 12. The inflatable ball as claimed in claim 7, wherein said valve-retaining member is made from a material different from the material of said outer bladder.
 13. The inflatable ball as claimed in claim 7, wherein said slit-type valve is made from rubber. 